Production of motor fuels



Feb. 3, 1948.

Resishance s. H. MOALLISTER ET AL 2,435,402

PRODUCTION OF MOTOR FUELS Filed Dec. 14, 1958 1nven+ors:

Sumner HMcAHiS+er Edwin F. Bullard 5g iheir AHorneg:

Patented Feb. 3, 1948 UNITED STATES PATENT OFFICE monucrron or MOTOR wens Sumner n. McAllister, Lafayette, and Edwin F. Bullard, Oakland, Calif., assignors to Shell Development Company, San Francisco, Calif., a

corporation of Delaware Application December 14, 1938, Serial No. 245,114

13 Claims. (01. zoo- 33.4)

This invention relates to a low temperature process for reacting isoparafllns with olefines in the liquid phase in the presence of catalyst acid, particularly sulphuric acid, to form higher boiling hydrocarbons. It deals particularly with a new and more efficient method for carrying out such reactions in a continuous manner in which undesirable side reactions may be minimized.

An important object of our invention is the provision of a continuous process for reacting novel process is to reduce to a minimum the power required for dispersing the reactants in the catalyst acid while insuring complete, uniform and intimate dispersion. It is also-an object of our invention to provide a method of operation which makes practical high rates of production per volume of reaction space.

The process of our invention provides anespecially advantageous method for reacting lower boiling isoparaffins such as isobutane and isopentane with normally gaseous olefines such as propylene, normal and/or isobutylenes to form paraffins which boil within the gasoline range and have a high anti-knock value. It will be understood, however, that our new reaction method is not limited to these specific reactions but may advantageously be used in the manufacture of other branched chain saturated compounds by reacting saturated hydrocarbons having a hydrogen atom attached to a tertiary carbon atom, whether normally gaseous or liquid, such for example as 2-methyl pentane, 2,3-dimethyl butane, 2.2,3- trimethyl butane, 3-ethyl pentane, methylcyclo- .pentane or suitable substitution products thereof such for example as monochlorides corresponding thereto or the like, with the same or other oleflnes. Olefines which may be reacted with such compounds in accordance with the process of our invention include, in addition 'to propylene and the butylenes, alpha and beta amylene, isopropylethylene, trimethyl ethylene, unsymmetrical methyl ethyl ethylene, isobutyl-ethylene, isooctylenes, cyciopentene, cyclohexene, butadiene, A cyclohexadiene. or the corresponding unsaturated chlorides, and the like. The reactants may be used ina pure state as a mixture of one or more isoparafflns with one or more oleflnes or as such mixtures containing other components which may or. may not-be inert under the reaction conditions but which are such that they do not interiere with the desired reaction between the iso paraflln or isoparamns andthe olefine or olefines being reacted. Thus hydrogen, nitrogen, methane, ethane, propanelnormal butane, tetramethyl methane, ethylene and the like, for extertiary olefine or" oleflnes'rnay be selectively iprincipally secondaryoleflne' or starting material for ample, may be present. Particularly advantage ous sources of isoparafllns andoleflnes which may be reacted in accordance with the process of our invention are hydrocarbons derived from pctroleum,petr01eum productashale oi s. coal e t. animal or vegetable oils or like carboniferous materials, The isoparafllnsand/or olefines present in the starting material maybe of natural occurrence, the resultoi catalytic dehydrogenation, cracking or other pyrogenetic treatment. Cracked petroleum distillates or special iractions thereof, particularly hydrocarbon'fractions consisting of,

'or predominating in, hydrocarbons containing the same number of carbonatoms per molecule, may be used althoughnon-isomeric mixtures are. also suitable. Such hydrocarbon fractions or inixtures may advantageously subjected to a polymerization treatment prior to their treatment in accordance with the process or the present invention. For example, the mixture may be first treated to interpolymerize tertiary oleflnes with secondary oleiines and the residual hydrocarbon containing isoparaflin and olefines, generally our process. Copending applicationSerial No. 133,203 of Sumner H. Mc- Allister filed March 26, 1937 now United States Patent 2,174,247, describes an especially advantageous method for carrying out such a preliminar interpolymerization step. Alternatively polymerized in part or substantially quantitativelyprior to carrying out the present process 'vlvith ':the' residual isoparaflln United States Patents 1,938,177; 2,007,159 and and oleflne content.

2,007,160 describe suitable methods for carrying out the preliminary removal of tertiary olefines. Whatever the preliminary polymerization treatment used, the present process may be carried out "with the remaining isoparaflln whether or not the olefine polymers are first separated therefrom. I

While we do not wish to be limited to any particular theory with respect to the present invenoleflnes used as ammo:

tion, the following explanation of the process of our invention will assist in making clear its method of operation and in explaining the highly advantageous results attained. The isoparaflin is considered as the less reactive molecule and the olefine as the more reactive molecule involved in the process of our invention. In the presence of an acid catalyst, such as sulphuric acid of at least 90% concentration or its equiva' lent, the olefine can be made .to react with the isoparafiln. The reaction y be considered as life of the catalyst. Relatively small amounts of i olefine are capable of leading to rapid deterioration of the acid catalyst. Oleilnes areabsorbed by catalyst acids at enormously faster rates than are isoparafllns. For example, the rates of absorption of alpha and beta butylenes in 97% sulphuric acid at 25 C. are about 620 and 740 times, respectively, that of isobutane. This greatly increases the dimculty of protecting the catalyst acid from undesirable olefine absorption. We have found. however, that the rate of absorption of olefine may be materially reduced by proper dilution of the olefine and that it is particularly desirable to dilute the olefine feed with the isoparaflln to be used in the reaction as in this way longer catalyst acid life is possible. At the same time it is highly advantageous to provide conditions favorable for high rates of isoparaflln absorption, such as strong acid solutions, and in particular by having large amounts of isoparamn, preferably in high concentration, present in the reaction zone. Merely having an excess of isoparaflin present is alone not sufllcient to insure along catalyst life and provision should be made for substantially complete reaction of the olefine in order that there may be no accumulation of olefine in the system. We have discovered that, contrary to prev ously held ideas, the reaction between iso araflins and olefines to form higher bo l n saturated hydrocarbons can be made a relatively rap d one,

Ba ed on these discoveries we have developed an efllc ent. techn callv practical met od for continuously reacting isoparafllns with olefines wh ch ives lone catalyst life and extremely hi h rates of production per volume of reaction space while insuring hi h yields of uniformly high quality oducts. In our process the ratio of isoparafilin tn olefine in the react on zone is advan ag ously ma n ained higher than that in the feed. Th s more favorable react on condit on is ac e ed by re yclin 2. part of the reacted mixture r ch in isonaraflln. but substantially free from olefi es. to m x with the feed as it enters the reactor. In our referred method of carrying out our process we advantageously operate with two stages of dilution of the olefinic feedfflrst diluting the olefine feed stock with isoparaflln-containing hydrocarbon before bringing it into contact with the catalyst acid and thenadding this mixture to recycled reaction mixture of dispersed catalyst and isoparaflln-containing hydrocarbon which is substantially olefine-free. In any case we prefer to operate with a high concentration of the isoparamn which it is desired to react in contact with the catalyst acid and present in excess over the olefine used. By this method of operation and the proper adjustment of contact time, acid strength, temperature and acid to hydrocarbon ratio complete reaction of the oleflne is readily achieved and we flnd it feasible to so operate that in the reactor proper the olefine concentration is so low that it is not measurable by existing analytical methods. To this end, it is highly advantageous to provide thorough. uniform, positive mixing of a small amount of olefine in a large amount of is-oparaflln so that no short circuiting or accumulation of olefine anywhere in the system takes place.

While other methods of operation may be used without departing from the spirit of our invention. the accompanying drawing illustrates, diagrammatically, one assembly of apparatus particularly suitable for large scale application of the process of our invention, in which optimum reaction conditions can be readily maintained. In the drawing pipe lines I and 2 are supply lines for isoparaflln and olefine containing hydrocarbon, respectively, from sources not shown, which are mixed in line 3. The rate of feed of the resulting mixture may be regulated by adjustment of valve 4. In line 3 the isoparaflln and olefine feed may be diluted with isoparaflin containing hydrocarbon introduced through lines 25 and/or 32. The feed from pipe 3 is introduced into line 5 where it contacts recycled reaction mixture comprising catalyst acid, preferably sulphuric acid, and unreacted isoparaflin. It is highly desirable that the mixing at this point be as thorough and rapid as possible. Line 5 is in communication with positive circulating means such as pump 6 which passes a part of the mixture of hydrocarbon and catalyst by lines 1, 8 and 9 to a means for maintaining the mixture in a dispersed condition until reaction is substantially complete which may take the form of time tank I ll or the like. A branch line H leading to cooler l2 permits cooling sufficient of the reaction mixture by indirect heat transfer to a suitable cooling medium, to bring the temperature of the entire mixture to the desired point after reintroduction of the cooled port on via line l3 connecting cooler H with line 9. The amount of reaction mixture circulated throu h the cooler instead of via line 8 may be regulated by inserting a suitable resistance ll which may take the form of an orifice plate or the like in l ne 8. The circulating stream of reaction mixture passes by line 9 to a time tank I0 which advanta eously may be equipped with perforated plates so spaced that they provide a. degree of turbulence sufllcient to maintain the des red dispersion of catalyst acid and hy rocarbon throu hout the time of res dence of the mixture in the tank althou h suitably packed towers or coils of pipe of suitable diameter and length or other eouivalent means may be used. From the time tank 10 the reaction circulates by line I 5 to line 5 where it a ain contacts incoming isoparaflln and olefine feed from line 3. Before such contact. however. a side stream is withdrawn by line I6 to means for separating imm scible liouids such as stratifler I! where stratification takes place and the upper, hydrocarbon layer is removed through pipe line iii. The lower, catalyst acid layer is returned to the circulation system by line l9 connecting separator I! with line 5 at a point on the down stream side of, and advantageously substantially removed from, the

hydrocarbons present.

point of connection of feed inlet line 3. The proelement to operate exclusively on hydrocarbon or on acid phase as it is difilcult to provide materials equally resistant to both phases. Thus a line 24 may be provided whereby a part of the stream of acid from separator I! can be taken off and used to seal the stufflng box of pump 6. Alternatively hydrocarbons can be'used by directing part or-all of the feed from lines I and 2 to the pump stufling box.

It is a feature of the process of our invention, that the acid catalyst used is preferably preconditioned before the start of the reaction by being first saturated with olefine-free hydrocarbon, preferably hydrocarbon containing the iso parafiln to be used in the process. To this end. the apparatus. in starting operations, is first charged with isoparafiln containing hydrocarbons, free from olefin'e. and the required amount of catalyst acid, for example, sulphuric acid of 90 to 110% concentration, is then added. In general a ratio of about 0.2 to about 2 volumes of acid phase per volume of hydrocarbon phase may be used, although ratios of about 0.4 to about 1.2, such that the hydrocarbon constitutes the continuous phase in the resulting dispersion, are preferred as ease of dispersion is facilitated thereby, but higher and lower ratios may be used; although excessively high acid ratios which resuit in too great a decrease in the volume of hydrocarbon in the recycle stream are undesirable. With the dispersion of sulphuric acid and isoparaflin hydrocarbon flowing uniformly through the system, valve 4 is opened and the olefinic feed, preferably containing at least an equal molecular amount of isoparaflin and preferably containing an excess of isoparamn, most preferably at least 3 molecules of isoparaffin per molecule of olefine is admitted through line 3. The rate of feed of reactants is preferably so adjusted with respect to the rate of fiow of recycle stream through line 5, that the ratio of isoparafin to olefine at the point of contact of acid and oleflne is of the order of at least 20 to 1 and more preferably is at least 50 to l. Ratios of abou" 100 to about 400 to l and higher may be used; it being only undesirable to employ such high ratios that the plant capacity is unnecessarily reduced.

In order to obtain high reaction rates, the sulthe main circulation stream instead of in a branch thereof as shown in the drawing, the choice of location depending upon the fiow rates most suitable for the particular cooler used.

It is not essential to have complete separation of hydrocarbon and acid in separator I! but it is highlyadvantageous to prevent removal of acid from the system with the hydrocarbon phase withdrawn through line l8. Should loss of acid occur in this or any other way, e. g. leakage, chemical reaction, etc., make up acid may be added, for example, through valved line connecting line l9 with an acid supply not shown. It is desirable to continuously or intermittently replace a part of the acid in the system, which may be withdrawn thru valve controlled line 21,

by fresh or suitably purified acid added thru line 20, although periodic draining of all the acid from the reactor and its replacement with fresh or purified acid, may also be used. Increased amounts of products boiling higher than the initial reaction product are usually associated with the falling off in conversion rate which is indica tive of the desirability of replacing catalyst acid. Emulsification difllculties and sulphur dioxide evolution can be overcome by replacing catalyst acid.

The hydrocarbon phase withdrawn from separator I! through pipe line It is conducted by line 26 to a distillation unit 21 for recovery of reaction product. Although it is not essential to the process of our invention, a part of the withdrawn hydrocarbon phase may advantageously be taken of! by line 25 before such distillation and used to dilute the olefine-isoparafiin'feed in line 3. In still 21, which may be of the flash distillation type, the higher boiling products phuric acid should be thoroughly mixed with the The circulation rate should be such-that the desired degree of mixing is maintained for suflicient time to allow the reaction of substantially all of the added olefine during one cycle of flow. It is highly desirable that no substantial recycling of unreacted olefine takes place. The proportion of reaction mixture diverted to cooler i2 and the degree of cooling therein are preferably adjusted so as to maintain a temperature of about 0 C. to about 35 ('2'. preferably about 15 to'25 C. in time'tank It. One efiect of recycling reaction mixture is to so increase the mass of liquid circulating through the time tank that only a small temperature rise results from the heat of reaction and of friction. Such heat can be removed efliciently at any one point and the cooler can be ofthe mostefllcient type and can be located in formed in the reaction are taken oil as bottoms thru line 28 while the unreacted hydrocarbon containing isoparafiin is removed by line 29. The unreacted hydrocarbon thus recovered may be returned to the reaction system, preferably with the olefinic feed as by lines 30 and 32. Where inert components are present these may advantageously be removed before returning the isoparaflin content to mix with the olefine feed. In the drawing the removal of inert components having a higher boiling point than the isoparaifin being used in the reaction, for example the removal of normal from isobutane, is illustrated. In such a case the overhead product from still 2! is fed to still 3i from which the isoparai'lin is removed by line 32 and returned to pipe line 3 while the inert component or components are withdrawn from the system by line 33. It will be obvious that depending upon the boiling points,

relative solubilities, etc. of the isoparaflin and mert material, other distillation methods or extraction or other suitable procedures may be used for removal of the inert material. The particular combination of operating conditions to be used in any particular case will de-.-

pend upon the isoparaflin and olefine or mixturethereof to be reacted. In all cases we prefer:- to operate under suflicient pressure to maintain. the reactants in the liquid phase. We also prefer -to use acid concentrations which are as high as possible in order to promote absorption of ISO!- paraifin therein. With sulphuric acid catalysts the upper limit of acid concentration depends upon the temperature employed as too high a concentration of acid at too high a temperature leads to undesirable sulphonation reactions and the like. Fuming sulphuric acid at temperatures below (1 C. may be used. The tendency of sul-' 7 phuric acid catalysts to cause sulphonation may be reduced by the use of phosphoric acid. Solutizers for the isoparaflin being reacted, such as benzene sulphonic acid and the like may be used with the catalyst acid as may also inorganic salts such as heavy metal sulphates which have a beneficial influence on the reaction. Sulphuric acid of less than about 90% concentration is preferably not used and for the reaction of iso- 8 feed stock are preferably avoided. We find it convenient to use the spent catalyst acid, preferably after dilution with water, e. g. to about 60 to 75% or lower. to remove such undesirable components from the feed stock but other suitable methods whether of the solvent extraction type or not may also be employed.

The following tables show the advantageous results obtainable by the process of our invention Yield as per cent of olefine fed. 14 Volugies oi product/volume of ac! Percent of product boiling between 24 and 132 Initially After advols. of product/vol.

oiaei After 6.75 vols. of product] butane with normal butylenes acid of about 96 to l0 as applied to the reaction of isobutane with butyl- 110% concentration, preferably 98 to 102% is enes, and th effect of diiierent operating condidesirable. Temperatures between 35 C. and tions thereon. The reactions were carried out in -20 C. are suitable. With the preferred 98 to a bronze turbo mixer of 1160 cc. capacity pro- 102% sulphuric acid a temperature of 0 C. to vided with a cooling coil through which cold C. is advantageous, higher temperatures being 5 acetone was circulated at a sufllcient rate to applicable with weaker acid and lower temperamaintain the desired tempe e mixer tures being desirable with more concentrated was provided with inlet lines for isoparaflin-oleacid. The diiference in reactivity of difierent fine feed and returned acid and a draw-01f line .isoparaiiins does not appear to be as great as d ng to a fifie f f which pp y the difi'erence in reactivity of the various olecarbon phase was continuously removed while fines. Thus where the same olefine or olefines lower acid phase was taken off by the acid return are used substantially the same reaction condiline. The isopfl fl n and fi e o eaction tions may be successfully employed for th reacwere continuously fed to the reactor under a prestion of isopentane therewith as when isobutane re of a o t o .200 qgauge. at is used. When isobutylene is substituted for 5 a rate controlled by a thermo flow meter. Hybeta-butylene, for example, on the other hand, drocarbon phase was withdrawn from the sepit is advisable to alter the operating conditions arator at the same rate and distilled and the to compensate for the much greater reactivity e ct Ofl p d ct a d unreacted y c bOn reof the tertiary olefine. We prefer, when using covered and analyzed. In all cases the acid used highly reactive olefines to increase the ratio of 30 as Catalyst W s Sat With obutane free isoparafiin to oleflne used, particularly in the feed from olefine before the start of the run. The mixture to the reactor but also advantageously effect of premixing the olefine feed with isoparafin the reactor as well. Where propylene is used fin is shown in Table I.

Table I Exp. No 22 27 2s 36 Mols of isobutane added to the 4.8.

feed per mol of butylene fed.

Olcine concentration of mixture 14.0%.

Sulphuric acid catalyst concon- $6.3.

tratlon (wt. H280).

Volume ratio of acid to hydro- 0.7/1.

carbon.

Temperature 20 Feed rate (cc. of hydromrbon/ 90/100.

min.).

Contact time vol. ui acld. Aitcr 8.75 vols. of product] vol. of acid. Condition of catalyst at end of Almost completely Veryactive. Apparently not Veryactive. Capable Substantially although still test. spent. more than half its effective oi producing about 9 not completely spent.

life utilized. more vols. of prodas one of the reactants due allowance must be made for its diiTerent reactivity. When olefinic mixtures such as are obtained in Dubbs' crack- I ing processes are used the conditions should be adjusted with particular reference to-the more reactive olefine present. The differences in reactivity of secondary olefines of six or more carbon atoms per molecule are not so pronounced and it has been found satisfactory to react cracked gasoline with isobutane to obtain a saturated gasoline of high anti-knock value by using conditions quite similar to those employed when reacting isobutane with butylenes.

Presence of alcohols, ethers. ketones, etc., which tend to split off H20 in the presence of H2804 is undesirable because of the diluting effect of such decomposition product on the acid. Likewise nitrogen bases, such as amines, etc. in the These results show the advantage of feeding a high ratio of isoparaffin to olefine, it being apparent that doubling th ratio of isobutane to butylene in the feed under otherwise similar conditions not only greatly increases the yield (from 6.75 to an estimated 23 volumes of product per volume of acid) and gives better yields (192% compared with 148% based on the amount of olefine used) of better quality products but also makes feasible production rates not feasible when the lower isoparaffin to olefine ratios are used. The importance of having a high ratio of isoparaflin to olefine in the feed is clearly brought out by a comparison of the figures in columns one and four of Table I which are results of tests in which the ratios of isoparaflin to olefine in the reactor were approximately the same, the lower isoparaflin-olefine ratio in the first case emo:

being nearly compensated for by the lower recycle ratio of the latter. We consider it particularly advantageous to maintain a high concentration. suitably at least 40% and more preferably 50% or higher, of the isoparaflln or isoparaflins being reacted, in the hydrocarbon phase of the reaction mixture.

In Table II the effect of acid concentration and temperature on the reaction of isobutane with a butylene mixture containing beta butylene as the predominating olefine together with smaller amounts of iso and alpha-butylene. is shown.

Table 11 Exp. No- 34 29 33 35 30 81 87 M01: of isobutane added to the feed per moi of 4.0 4.8-"... 4.0 4.9 4.8.

butylene lerl.

Olellne concentration of mixture ied 10.0..... 11.3..... l0.9..- ll.0.-.. 11.1. Sulphuric acid catalyst cone. (wt. H1804) 92.1%... 94.. 06.8 96.7..." 100. Volume ratio of acid to hydrocarbon".-. 0.711--. 0.7/1. Temperature 2o 10 0 Feed rate (cc. of hydrocarbon/min.) -36.... 30-35.... 00-70.... 30-35 Contact time 20 min 2 2)-... 10 20. Yield as per cent of oleflne f 153 180.-. 180 216. Volumes of Product/volume of Mid 1.67- 10.32..-. 18.32-- 9.70. 0.97. Per cent of product boiling between 24 and 132 Initially 29.1"--- 80.5"--. 89.6..- 80 .2.

After 3 vols. of prod./vol. oi acid 80 5 87.8. 80-2--. .7.

After 6.75 vols. of prodJvol. of acid 69-1".-. 84.0. 72.4-.." .3.

After 8.75 vols. oi prod/vol. 0! id 67.0"... 80.7. 59.6.- .0.

Fmi 39.2- 30 46.7""- 53.2--- 80.1 92.0. Condition of catalyst at end of test Spent... Spent... Spent.-. Bpent.-- Still active...- Still active.

. These results bring out the desirability of using strong acid and suppressing sulphonation by operating at low temperatures. They also show the extremely long life of the catalyst when our method of operation is employed. The high production rates obtainable by our process are shown; for example, by the test reported in the last column of Table I, where the rate of production of higher boiling hydrocarbon was 1.01 volumes per hour per volume of reaction space.

It will thus be evident that our process for reacting isoparaiiins with olefines ofiers many advantages particularly in efllciency of operation and economy of catalyst acid. It not only provides a simple method, recycling of reacted'mixture, for maintaining a high ratio of isoparaflin to olefine but also permits of thorough mixing and the maintenance of the reaction mixture in a highly dispersed condition, at which the rate of reaction is high, for sufiicient time to allow the reaction of the olefine to go to completion. Furthermore, the ower required for maintaining such dispersion may be supplied by a pump of high efficiency in which the wear, which is a function of the power losses within the pump, is low, the power imported by the pump to the circulating mixture being converted into dispersing eiiect in the reactor, e. g. at theperforated plates of the time tank, and also advantageously in substantial amount at the juncture of lines 3 and 5. Our system provides ready control of the volumetric ratio of catalyst acid and hydrocarbon phases, since by the removal of product from the system without removing acid a definite constant quantity of the latter is maintained in the system. In this way operation in the preferred range of continuous hydrocarbon phase where greater opportunity for diffusion of reactants exists is readily maintained. In our preferred form of reaction system the feed inlet and product outlet points are separated by time tank elements or pipe coils or the like, the feed most preferably entering the recycle stream directly after the point of offtake of the separator branch, and consefurther reaction between the product and more olefine. All of these factors contribute to make our new process highly eflicient and economical and make its products superior in quality.

while we have described our invention in a detailed manner and illustrated suitable means of carrying it out it will be understood that variations may be made not only in regard to the isoparaflins and olefines which may be reacted and the catalyst acid used therewith but also with respect to the details of operation used. For example, while addition of isoparaflin to the olefinic feed has been described as our preferred method of operation, it is also possible to make such addition to the reaction mixture separately so as to maintain therein the desired high concentration of isoparaffin. Also instead of using the process for the primary production of relatively low boiling isoparafiins by reaction of one molecule of olefine with one molecule of" isopa'raflin, higher boiling products may be prepared by maintaining such a high concentration of such primary products in the mixture that their further reaction with another molecule of olefine is promoted. While emphasis has been placed on our preferred method of continuous operation it will be obvious that many features of our invention are also highly advantageous when operating intermittently or batch-wise. Again where return of unreacted hydrocarbon containing normal parafllns substantially inert under the conditions of our reaction has been described, it will be understood that in many cases such compounds can be advantageously isomerized, for example by passing their vapors over aluminum chloride catalyst at an elevated temperature, either after separationv of such compounds in still 3! or not, before such return to the system, and the resulting isoparaflins used in our process. Still other modifications may be made in the process of our invention consequently no limitations other than those imposed by the scope of the appended claims are intended.

The herein disclosed method of alkylating an 11 Darafiin with an oleflne in the presence of an alkylation catalyst while maintaining the ratio of said isoparaflin to olefine at the point where the olefine initially contacts the catalyst at least 50 to 1, preferably above 100 to 1, and simultaneously maintaining the concentration of the isoparafiin in the hydrocarbon phase of the reaction mixture above 50 preferably above 60%, by liquid volume of the hydrocarbons, isclaimed in copending application Serial No. 671,988, filed May 24, 1946, as a division of t e present application.

/Weclaim as o r invention:

1. A process of producing an alkylation product from an isoparafiin and a mono-cyclic olefin having to 6 carbon atoms in the ring which comprises contacting an excess of isoparamn, said cyclic olefin and concentrated sulfuric acid under alkylation conditions at which reaction between said isoparaffin and olefin takes place and a saturated hydrocarbon is produced.

2. A process of producing an alkylation product from an alkyl cycloparaflin anda mono cyclic olefin having 5 to 6 carbon atoms in the ring which comprises contacting said cyclic olefin, an excess of said cycloparaflin and concentrated sulfuric acid under alkylation conditions at which reaction between said cyclic paraffin and olefin takes place and a saturated hydrocarbon is produced.

3. A process of producing an alkylation product from an alkyl cycloparamn and an olefin which comprises contacting said olefin, an excess of alkyl cycloparafiin and concentrated sulfuric acid under alkylation conditions at which reaction between said cyclic paraflin and olefin takes place and a saturated hydrocarbon is produced.

4. A process for the production of an alkylated hydrocarbon which comprises reacting an isoparaffin with an aliphatic mono-olefinic hydrocarbon chloride in the presence of concentrated sulfuric acid and correlating the amount and concentration of sulfuric acid and the proportion of isoparaifin and aliphatic mono-olefinic hydrocarbon chloride to effect alkylation of the isoparafiin by said unsaturated chloride as the principal reaction.

5. In a process for reacting an isoparaflin with an olefin in the presence of concentrated sulfuric acid, the improvement which comprises adding to the sulfuric acid catalyst an amount of benzene sulfonic acid sufilcient to promote alkylation of said isoparafiln by said olefin.

6. A process for alkylating a low boiling isoparafiin which comprises reacting said isoparafiin with an olefin in the presence of concentrated sulfuric acid and an aromatic sulfonic acid.

7. In a process for reacting an isobutane with an olefin of at least three carbon atoms per molecule in the presence of concentrated sulfuric acid, the improvement which comprises adding to the sulfuric acid catalyst sufiicient of an arcmatic sulfonic acid to promote alkylation of said isoparafiin by said olefin.

8. A process for the production of an alkylation product from an isoparaflin and an aliphatic olefinic chloride which comprises contacting an excess of isoparaffin and said olefinic chloride with an alkylation catalyst acid under alkylation conditions at which reaction between said isoparafiin and olefinic chloride takes place and a higher boiling branched chain saturated compound is produced.

9. A process for the production of an alkylation product from isobutane and an olefinic chloride I .which comprises contacting an excess of isobu- 12 tane and said olefinic chloride with an alkylation catalyst comprising concentrated sulfuric acid under alkylation conditions at which reaction between isobutane and said olefinic chloride takes place and a branched chain saturated compound is produced.

10. A process for the production of an alkylation product from a monochlorinated isoparafiin and an olefinic compound of the group consisting of olefinic hydrocarbons and the corresponding unsaturated chlorides which comprises contacting said monochloride and olefinic compound with an alkylation catalyst acid under alkylation conditions at which reaction between said monochloride and olefinic compound takes place and a higher boiling branched chain saturated compound is produced.

11. Process of making isooctanes from isobutane and butene which comprises alkylating said isobutane with said butene in contact under alkylating conditions with a catalyst comprising concentrated sulfuric acid and phosphoric acid, said catalyst containing less than 10% of water.

12. In a process of alkylating a saturated tertiary carbon atom-containing hydrocarbon by reaction with an olefinic compound of the group consisting of olefinic hydrocarbons and the corresponding unsaturated chlorides in the presence of concentrated sulfuric acid, the improvement which comprises maintaining a circulating stream of a dispersion of catalyst acid and saturated tertiary hydrocarbon-containing reaction mixture, feeding into said stream of circulating dispersion said olefinic compound and stoichiometric excess of saturated tertiary carbon atom-containing hydrocarbon, withdrawing a portion of the reacted dispersion while recycling remaining dispersion having the same composition to contact with the reactants, separating the withdrawn dispersion into a phase containing alkylation product and excess unreacted saturated tertiary carbon atom-containing hydrocarbon and an acid phase, dividing said separated alkylation product-containing phase into two streams each having the same composition, re-

f cycling one of said separated alkylation productcontaining streams to mix with the feed of said olefinic compound before it contacts the acid whereby a substantially higher ratio of said saturated tertiary carbon atom-containing hydrocarbon to said olefinic compound is maintained at the point of contact of said olefinic compound with the acid than is present in the feed, fractionating the other of said alkylation productcontaining streams to sepamte the alkylation product from the excess unreacted tertiary carbon atom-containing hydrocarbon present therein and returning the latter to mix with the feed.

13. In a process of alkylating a tertiary carbon atom-containing saturated compound of the group consisting of saturated hydrocarbons and monochlorides having a tertiary carbon atom by reaction with an olefinic hydrocarbon in the presence of an alkylation catalyst comprising concentratedsulfuric acid and a stoichiometric excess of said saturated tertiary carbon atom-containing compound, the improvement which comprises maintaining an emulsion of said catalyst acid and reaction hydrocarbon circulating in a reaction zone, feeding into said circulating stream the olefinic hydrocarbon together with a, stoiehiometric excess of the saturated tertiary carbon atom-containing compound to be alkylated,

withdrawing a part of the reacted emulsion from 13 the reaction zone while returning nemainina emulsion to contact with said reactants in the reaction zone, separating the withdrawn emulsion into a phase containing alkylation product and excess unreacted saturated tertiary carbon atomcontaining compound and an acid phase, divid in; said separated alkylation product-containing phase into two streams each having the same composition, recycling one of said separated alkylation product-containing streams to mix with the feed of said oieflnic compound before it contacts the acid whereby a substantially higher ratio or said saturated tertiary carbon atom-containing compound to said oleflnic compound is maintained at the point of contact 0! said oleflnic compound with the acid than is present in the feed, and recovering the alkyiation product from the other of said aikylation product-containing streams.

SUMNER. H. McAIl-IBTER.

EDWIN 1". BUILARD.

nnrnnmucas crran J The ioiiowing references are of record in the I UNITED STATES PATENTS Number Name Date 370,688 Trade-Hark Apr. 2. 1940 2,001,910 Ipatiei! May 21, 1935 2,161,392 Stevens et ai. June 6, 1939 2,169,809 Morreii Aug. 15, 1939 2,211,747 Goldsby et ai. Aug. 13, 1940 2,398,486 Ballard Mar. 12, 1948 FOREIGN PATENTS Number Country Date 479,345 Great Britain Jan. 31, 1938 824,329 France Nov. 10, 1937 me of this patent: 

